1. Technical Field
The present invention generally pertains to a system for mounting components to a vehicle body. More particularly, the present invention relates to a mechanism providing a hard mount through a plastic body panel for positive constant torque retention of hinges and other highly loaded body components.
2. Discussion
The use of plastic body panels within motor vehicles is on the increase due to the reduced weight, reduced cost, and increased formability of plastic in relation to steel. However, most of the plastic materials used in manufacturing motor vehicle structures do not exhibit the strength of their steel counterparts. Accordingly, when a highly loaded mechanical joint, such as the interconnection of a passenger door hinge and a vehicle body, includes a plastic body component, the mechanical integrity of the joint suffers. For example, many plastics will yield when placed under the load required to support the door. Depending on the compound used, the yielding process may rupture or otherwise cause the plastic component to fail.
The concern regarding low compressive strength has been previously addressed by embedding a metal reinforcement within the plastic component. In one example, a metal sleeve is molded into the component and a fastener is disposed within the sleeve to mount the component. This design has its disadvantages. Specifically, the plastic material encapsulating the metal insert creeps over time due to the high loads required to securely attach certain components to the vehicle. Once the plastic material flows from the area beneath the bolt head, the body of the bolt is no longer extended the desired amount. As such, the clamp load originally exerted by the bolt is substantially reduced, possibly leading to vibratory loosening and joint failure.